Association study for Parkinson's disease and a dopamine transporter gene polymorphism (1215A/G).

The dopamine transporter (DAT) may play a role in the pathogenesis of Parkinson's disease (PD) because dopamine-specific neurotoxins are taken into dopaminergic nerve terminals via the DAT. A recent study has demonstrated that a DAT polymorphism in exon 9 (1215A/G) is associated with susceptibility to PD. This finding was not replicated by another study, however. Therefore, the significance of this association was tested using a Chinese sample population consisting of 102 PD patients and 174 controls, together with the association for onset age. Comparing the two groups, neither the genotypic (p = 0.272) nor allelic frequencies (p = 0.209) were statistically different. Further, the mean onset age was not significantly different for PD patients comparing the DAT genotypes (p = 0.925). Our findings confirm those of the previous negative report and, taken together, suggest that the DAT polymorphism (1215A/G) does not play a major role in the susceptibility to PD. Other DAT genetic variants, and the association of these variants with PD symptomatology or treatment response, may merit further investigation. Copyright 2002 S. Karger AG, Basel